Weedness of uncultivated land in the Polessye zone of Ukraine

Abstract

Goal. Clarification of the species of vegetation on uncultivated lands of Polessye, Zhytomyr region, which have been withdrawn from agricultural use for a long time. Methods. Field research, expedition — route observations, statistical analysis. Monitoring of vegetation of lands that came out of agricultural use and the study of species of plant groups was carried out during 2011—2015 in the southern Yemilchyn and Novohrad-Volynskyi and northern — Ovruch and Narodytsky districts of Zhytomyr region. Results. The vegetation cover of uncultivated lands of Polessye part of Zhytomyr region has been studied. During the years of non-use of land in agricultural circulation, separate micro-groups of plants have been formed, the area of which is gradually increasing. Six microgroups belonging to two associations were identified and studied. The first association of Poo-Festucetum pratensis was on a close-knit medium-high mane, which included three microgroups with a predominance of meadow oatgrass, meadow clover, and common viper. The second association, Poopalustris-Alopecuretum pratensis, was found on lowland plains and included microgroups with a predominance of meadow foxtail, mouse pea, and northern butterbur. It was determined that both plant groups of the surveyed areas were dominated (according to Raunkier) by hemicryptophytes — plants whose buds are at ground level or submerged up to 5 cm — 87.1 % in the southern and 91.3 % in the northern regions of Zhytomyr region. A smaller number of 3.2 and 8.7 % are hamephytes — plants whose buds are 20—30 cm above ground level. Conclusions. It has been established that uncultivated lands of the Polessye part of Zhytomyr region, under the influence of natural factors, are intensively transformed into unsuitable lands and reserves of malignant weeds, which cause a steady risk of constant threat of their spread to arable lands. Vegetation of lands withdrawn from agricultural use includes in the southern regions of Zhytomyr region. — Yemilchynsky and Novograd-Volynsky groups of weeds of 23 species from 21 genera, 13 families, in the northern districts — Ovruch and Narodytsky — 31 species from 26 genera, 11 families.